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Crane Codes

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EricaB

Nuclear
Jul 19, 2011
31
Hi, thanks for your inputs in advance.

I am working on modifying a crane that was orignally designed to EOCI Specification 61.

Since EOCI has been replaced by CMAA, I am wondering what the major differences between the code is so that I can provide reconciliation justification before moving forwards with the modification design.
 
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I don't know the differences in the two but do know that your crane will fall under the "Under Hook Lifting Devices" by OSHA if in the US.
Modifications to such devices did require written approval from the manufacturer if still in business. If the manufacturer is out of business one has to jump through hoops to keep out of trouble.
Even if the manufacturer is still in business it can still be a hassle Case in point we had two friction cranes, 75 and 100 ton, that required some repair by welding to the lattice work of the booms. We got permission to repair the 100 ton with essentially no problem. We were 3 months getting the repairs made to the 75 ton as it was a different manufacturer that required their service people to to the work. The service company didn't carry enough insurance to get on site, they had no welding procedures, and the wouldn't allow us to give their welder a plate test and had no understanding at all of the OSHA requirements. On the 75 ton crane it would probably been cheaper to but a replacement boom from someone like Essex.

I would contact the CMAA directly for their requirements along with getting a copy of the OSHA regulations.

You have to watch the regulations and as I have posted before we got our tail into big trouble with OSHA on two occasions. It is hard to explain to management why one little piece of paper is going to cost him a bunch of money.
 
Here is a little more information about what I am asking.

I work in the nuclear industry, this is a spent fuel handling machine (technically an overhead crane that runs over a pool and moves loads under water).

The project that I am working on requires that an auxiliary hoist be added for handling VERY light loads (< 500 lb). With that being said, I want to add the auxiliary hoist (jib crane) using CMAA Specification 74 but due to our licensing commitments to the NRC we have stated that this particular crane was designed entirely to EOCI Spec 61.

I need to provide code reconciliation for this modification to the extent that CMAA Spec 74 is similiar to EOCI Spec 61. The problem is I can't access this code ANYWHERE! I have contact MHIA who controls the CMAA code and they can not provide me with a copy of the historic code.
 
It appears as you posted that CMAA Specification 70 is a drop in replacemnt for EOCI Specification 61 EOT. This informaion is in the intorduction of the the linked Specification below. I see nothing that gives a line by line comparison.


Here is the only direct reference to a copy EOCI Specification 61 EOT in in the library listing in the following brochure.


This link might be of interest.

=AFQjCNGjUpJGfxmUGZDIyk6nxLd-kVfQVg

Are you talking about adding a second lower capacity hoist to an existing crane?

You mentioned jib, could you better definewhatyou are going to do?
 
Yes, the second hoist will be accomplished by adding a rotating jib crane to the existing crane structure to give the added reach needed to clear obstructions (bridge catwalk).

We need the second hoist so we don't have to switch the lifting tools out (very difficult to perform since it is over water and there is no access allowed into the pool itself for obvious reasons).

I have modified a few cranes before to add additional hoists however in those situations I was not bounded to an existing code requirement like EOCI. Those cranes were specifically in conformance with CMAA Specs.
 
Very late last night instead of counting sheep I remembered an
encounter with the NRC when they controlled Radiography
where we got gigged for having the wrong signs. The comment
was something like this "that rule has been superseded".

The reference in the CMAA Introduction in the link posted
previously uses the word supersedes. If you look at the legal
definition of supersedes it would essentially make EOCI
Specification 61 EOT null and void. This might be a talking
point.


i will keep looking for a copy of the EOCI Specification
 
NUREG-0612 does not apply since the hoist will be rated below the criteria to be considered a "heavy load".

If it were easy my job would be no fun.

 
NUREG-0612
"guidelines for the control of small loads near spent fuel"
 
I understand NUREG-0612 very well.

"a task should be initated to establish guidelines for the control of small loads near spent fuel"

This does not provide me with any guidance on the original intent of my question. However, thank you for the suggestion.
 
Thanks to those who responded, I have FINALLY found a copy of EOCI SPEC 61.

 
Just a thought. Since you are adding a second hoisting mechanism, you will probably need to derate the original hoisting mechanism.
 
Only if both hooks will be used at the same time: If procedures prohibit both at once, then that part of the cert won't change.
 
About the weight of the second hoist, wouldn't that impose additional loading on the bridge?
 
It's not as simple as adding a second hoist.

If I'm reading correctly, the proposal is to add a jib to the crane's traveler/crab/hoist carrier, with the jib hoist to be used while a load is suspended from the main hoist, and with the jib hoist's hook possibly well outside the transverse travel plane of the main hoist's hook.

Even a small jib crane imposes substantial moment loads on its substrate, effectively multiplying the hoist weight and the load by the length of the jib.

Single girder bridge cranes in particular are extraordinarily flexible in torsion, because they're not usually stressed that way, and the typical traveler's wheels are not designed to carry substantial moment loads to the bridge girder(s), because they're not usually asked to do so.

Some caution is advised.




Mike Halloran
Pembroke Pines, FL, USA
 
It appears the she wants to add a travelling jib crane to the bridge of an overhead crane. Yeah weight and moment must be included in the analysis.
 
Yes I am aware there is a lot to be designed on this project. We will be providing a full evaluation of the entire crane structure before we modify the crane. We can not derate the main hook. These are light load cranes to begin with (< 1ton), and I had to start with finding out how the original crane was designed. That was the intent of my original question, and now that I have the record code, the design is moving forwards.
 
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